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Dr Astroumoff's fabulous flying copepods
Ed Yong explains
One group of copepods, the pontellids, are found throughout the topmost waters. They tend to be more brightly coloured than other transparent members of the group. It’s thought that the colours help to reflect harmful ultraviolet radiation, but they could make the copepods more conspicuous to fish. Copepods escape from fish with powerful bursts of speed that propel them through the water. But those same movements can send them flying too...
... Their powerful escape reflex provides a lot of energy, but they lose anywhere from 58 to 88 per cent of that as they break the water surface. By contrast, a flying fish loses less than 0.1 per cent with the same manoeuvre. This is because the surface tension of water is much more important to a small animal than a big one... Still, their ‘flights’ are substantial. Each copepod is around 3 millimetres long, but their leaps carried them over an average distance of 80 millimetres. That’s well beyond their own body length. It’s also at least 3 times greater than the length of the pursuing mullet, and further than the fish can actually see. And the longest jumpers even managed to cover 170mm.
...[and] despite the energy needed to leave the water, the copepods travel so far in the air that they recoup their initial losses. To travel the same distance underwater, they would need to spend 20 times more energy.
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